Effects of Chitosan as the Growth Stimulator for Grammatophyllum speciosum in Vitro Culture

Authors: Sopalun K., Thammasiri K., Ishikawa K.

Abstract:

The effects of chitosan, a biodegradable polymer, were studied in Grammatophyllum speciosum protocorm-like bodies (PLBs) in vitro culture. The chitosan concentration of 0, 5, 10, 15, 20, 25, 50 or 100 mg/l were supplemented in half-strength Murashige and Skoog (1/2 MS) liquid or on agar media containing 2% (w/v) sucrose. The results showed that liquid medium supplemented with 15 mg/l chitosan showed the highest relative growth rate (7-fold increase) of PLBs. On 1/2 MS agar medium supplemented with 25 mg/l chitosan gave the highest relative growth rate (4-fold increase). The relative growth rate of G. speciosum PLBs on agar medium was significantly lower than that in liquid medium. Moreover, chitosan, supplemented to agar medium promoted shoot formation but not rooting. However, supplementation at too high a level, such as 100 mg/l can inhibit growth and kill PLBs.

Keywords: Chitosan, Grammatophyllum speciosum, Growth stimulator

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1061477

References:

[1] A. Pridgeon, The Illustrated Encyclopedia of Orchid. Kyodo Printing Pte Ltd, Devon, Singapore, 2003.
[2] G.M. Morel, Producing virus free Cymbidium. Am Orchid SocBull , vol. 29, pp. 495-497, 1960.
[3] K.L. Nge, N. Nwe, S. Chandrkrachang and S. Stevens, Chitosan as a growth stimulator in orchid tissue culture. PlantSci. vol. 170, pp. 1185- 1190, 2005.
[4] E.A. Barka, P. Eullaffroy, C. Clement and G. Vernet, Chitosan improves development and protects Vitis vinifera L. against Borytis cinerea. Plant Cell Rep, vol,. 22, pp. 608-614, 2004.
[5] K. Sopalun, K. Thammasiri and K. Ishikawa, Micropropagation of the Thai orchid Grammatophyllum speciosum blume. Plant Cell Tiss Organ Cult, vol. 101, pp. 143-150, 2010.
[6] A. Uthairatanakij, J.A. Teixeira da Silva and K. Obi Wan, Chitosan for improving orchid production and quality. Orchid Sci Biotechnol, vol. 1, pp. 1-5, 2007.